Self reliance for one who uses a wheelchair comes with a price. For example, a van provides a number of advantages over a two door or four door car, but a van is expensive. A modified van is even more expensive, since such a van may have accessories--or necessities--such as a wheelchair lift that contributes to the high cost of the modified van. One costly component of a wheelchair lift is the power mechanism or power mechanisms used to move the lift out from a stored position to an operating position, then to raise and lower the lift, and then to move the lift from the operating position back to the stored position.
For the modified van, an under vehicle lift (UVL) is most desired because it takes up no interior van space. Interior van space is at a premium even for families without a member in a wheelchair.
The purpose of a lift on a vehicle such as a van is to safely raise a person and wheelchair from ground level to the level of the floor of the van, where the person then wheels into the van. Then the lift is stored for travel to a destination, whereupon the lift is moved out to safely carry the person and the wheelchair from the van to the ground